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What's New In: Refrigeration units

Truck and trailer refrigeration is evolving as new regulations governing the transportation industry tackle the problem of pollution. There are already anti-idling laws in many states aimed at conserving fuel and reducing particulate matter (PM) emissions from diesel engines. Now the California Air Resources Board (CARB) is implementing another measure aimed specifically at refrigerated carriers that

Truck and trailer refrigeration is evolving as new regulations governing the transportation industry tackle the problem of pollution. There are already anti-idling laws in many states aimed at conserving fuel and reducing particulate matter (PM) emissions from diesel engines. Now the California Air Resources Board (CARB) is implementing another measure aimed specifically at refrigerated carriers that goes into effect at midnight December 31, 2008.

The TRU (Transport Refrigeration Unit) particulate rule, outlined in Article 8, section 2477 of CARB, states that refrigeration units with diesel engines that are seven years and older must be replaced, except if the unit has standby electric capabilities or, in the case of a refrigerated trailer, meets any of the approved VDECS (Verified Diesel Emission Control Strategies) that are posted on the web site.

According to Jerry Duppler, Thermo King product manager-trailers, this is a rolling regulation, the goal of which is to ensure all refrigeration units operated in California are never older than seven years and thus cleaner running. “As equipment ages,” he explains, “the thermal performance of the insulated truck body or trailer declines as the foam insulation deteriorates. That fundamental factor means older refrigeration units have to run longer and harder, burning more fuel and emitting more particulate matter.”


“On the other hand, because of EPA regulations imposed on us as manufacturers,” Duppler continues, “newer units coming to market feature the latest technologies so are, by design, cleaner running.” The CARB rule not only applies to trucks and trailers domiciled and operating in California, he adds, but also to all refrigerated vehicles outside the state whose routes bring them across the California border, even if only on rare occasions. It also applies to warehouse facilities and distribution centers where refrigerated trucks load and unload in California.

Tim Ryan, Thermo King product manager-diesel trucks, reports that the electric standby exception to the CARB rule makes sense, since typical applications for these vehicles involve loading and unloading product at central distribution locations that have electric standby capabilities and the infrastructure to support it.

“Also, when dropping off product in places like convenience stores, schools, hospitals, hotels, etc.,” says Ryan, “there are generally not a lot of other trucks unloading at the same time. So California is allowing fleets to run their refrigeration unit's diesel engine if there are two or less refrigerated trucks unloading product at the same time and location. If there are three or more, the operator must use his electric standby unit.”


Most of what applies to refrigerated trucks also applies to reefer trailers, notes Jerry Duppler. “Except we offer a few more solutions for this market, since it is larger.” One solution is a diesel particulate filter (DPF) that can be installed on the exhaust system of the reefer unit's diesel engine. It traps diesel particulates before they escape into the atmosphere.

“Another solution is to actually update the diesel engine on the refrigeration unit when it becomes older than seven years, which automatically brings the unit into compliance for the next seven years,” Duppler explains. “We've developed engineered kits to update older units to new engines.” These and other solution strategies are posted on the CARB web site under VDECS for fleets to review.

Thermo King, Duppler points out, also works with customers to help them optimize control and performance of their refrigerated units. “The use of software controls, in particular, can help them maximize fuel efficiency of the units, matching operation of the unit to the type of cargo being hauled. Cycle-Sentry, our term for operating a unit on a start-stop basis so the unit is running only when absolutely necessary, is not a new idea, but we are trying to make our controls more sophisticated so fleets can get very precise temperature control. This summer we will be introducing some software updates for our units that will optimize operation of the reefer unit with a focus on maximizing fuel economy.”

Tim Ryan adds that Thermo King has done a lot to help customers be more green. “We offer the electric standby option in straight trucks, which accounts for about 60% of the units we sell,” he notes. “Plugging the unit in for electric mode operation reduces emissions, noise and fuel consumption, and it prolongs the life of the unit. Another trend in trucks is toward hybrid electrification of the chassis itself. With that becoming a reality, at some point down the road you may also see reefers whose primary source of power would be electric, with perhaps a small diesel engine as backup or an engine that uses another source of fuel.”

Another area Thermo King is working on with alternative fuels is biodiesel. According to Duppler, the manufacturer's products are currently approved across the board for use with a B-5 biodiesel blend. Meanwhile, field testing of a B-20 biodiesel blend is also underway in hopes that it will soon be approved as well.

With all that it's doing toward helping fleets be more green, Thermo King also encourages fleets to get back to basics in conservation. Fuel and other resources, for example, could be saved by adhering to good practices like using door curtains to keep cool air inside the trailer and humid air out, and using door switches to automatically shut refrigeration units off when doors are opened.


Carrier Transicold is also focusing on greener product solutions. David Kiefer, product manager-trailer products, says this year both the U.S. EPA and CARB are requiring refrigeration unit manufacturers to provide cleaner-burning engines in their products. The primary target is PM, which the agencies want to reduce from diesel emissions through legislation.

“Our latest trailer and truck refrigeration unit engines are the cleanest ever offered by Carrier and are compliant with EPA and CARB,” Kiefer reports. “The engines in our trailer units generally improve [PM emissions levels] beyond the newly effective EPA Tier 4i requirements by 30%.”

Likewise, the engines in Carrier's Supra truck units emit 40% less PM than required by the EPA Tier 4 regulation that took effect in 2008. Kiefer notes that Carrier continues to work closely with U.S. EPA, CARB and its engine manufacturer, Kubota, to ensure customers are offered cost-effective and compliant product solutions to current and pending legislation. The manufacturer introduced new Tier 4i and Tier 4 engines for Carrier refrigeration units in March at the Mid-America Trucking Show.

Besides running cleaner, Kiefer says the engines used in Carrier's new trailer units are between 1% and 2% more fuel-efficient than the Tier 2 engines they succeed. They are also about 1 dB quieter.


According to Kiefer, the use of electric standby capability is considered an alternate strategy for conforming to CARB regulations. Carrier's hybrid diesel-electric Vector 1800MT multi-temperature system offers electric standby capability. Electric standby can also be optionally added to some Carrier single-temperature units. Another CARB compliancy alternate Carrier is currently pursuing is a DPF option.

“Over the last year,” Kiefer reports, “there has been increased interest among customers in Carrier's Vector hybrid product. Customers, especially distribution, grocery and dairy fleets, realize fuel savings can be substantial by plugging in their units while unloading at a dock.” In addition to being a CARB compliance option when proper recordkeeping is maintained, he notes the use of either a hybrid or an electric standby unit can reduce noise, emissions and maintenance costs on the equipment.

To maximize fuel economy, Carrier's Intelliset option was recently reintroduced to include eight preset factory performance configurations ranging from maximum temperature control to maximum fuel economy. Customers, Kiefer explains, “can best balance fuel use versus product protection depending on the particular cargo.

“As today's electronics become more powerful, Carrier has the ability to monitor and exert more control over the refrigeration unit via its Advance microprocessor,” he continues. “Customer tests and field trials with large fleets have led to software improvements that allow the units to significantly reduce fuel consumption while maintaining excellent temperature control.”

Kiefer says a key component for fleet operators is long-term cost of ownership. “The Carrier X2 Series and hybrid Vector system contribute to more uptime, reducing the number of assets the customer has to purchase and operate,” he notes. “Fewer maintenance items also means less maintenance costs, as well as less time out of service to perform maintenance.”


Carrier Transicold

Thermo King

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